1. Technical Field
This disclosure relates generally to an acoustic panel and, more particularly, to an acoustic panel for attenuating noise in, for example, a gas turbine engine.
2. Background Information
A gas turbine engine may include an acoustic panel for attenuating noise generated during engine operation. A typical acoustic panel includes a honeycomb core connected between a solid face skin and a perforated face skin. This honeycomb core includes a plurality of resonating cavities. The honeycomb core may have a thickness that tunes the resonating cavities to a specific target frequency of the noise to be attenuated. As a result, noise waves reflected by the acoustic panel may interact with noise waves traveling towards the panel. Differences in phase between the noise waves in an acoustic field adjacent the perforated face sheet may enable the reflected noise waves to destructively interfere with and attenuate the noise waves traveling towards the acoustic panel.
New engine designs may require acoustic panels to attenuate noise with relatively low frequencies while utilizing substantially the same or less space than previous panels. Attenuating low frequencies, however, may increase the thickness of the honeycomb core and, thus, the thickness of the acoustic panel. There is a need in the art therefore for an improved noise attenuating acoustic panel.